This is an application for support of a conference entitled Making and breaking the left-right axis: Laterality in development and disease to be held June 15-16, 2013 in Cancun, Mexico, just prior to the joint Society for Developmental Biology 72nd Annual Meeting and the 17th International Congress of Developmental Biology. The objective of this satellite symposium is to bring together researchers working on invertebrate and vertebrate models for an up-to-date presentation of the latest results on the development and disease relevance of left-right asymmetry. Although there have been many exciting recent developments in the field, a meeting on this specific subject has not been held since 2001, when a small workshop was sponsored by the Instituto Juan March in Madrid. Since then, numerous discoveries have been made on how sidedness is established and maintained in the embryo and the common disorders that can result from abnormal left-right patterning, such as ciliopathies, polycystic kidney and liver disease and complex congenital heart disease. New insights have also been obtained on the significance of laterality in the developing nervous system and its influence on behavior. The group of invited speakers will, for the first time, unite researchers working on left-right symmetry breaking in diverse developmental models and organ systems. The high degree of enthusiasm expressed by researchers who have already agreed to participate indicates the timeliness and level of interest for a symposium on this topic. We anticipate that this symposium will attract approximately 100 participants, with the size and format of the event encouraging maximal interaction among the attendees. The co-organizers will also inform the scientific community more broadly by serving as guest editors of a journal issue dedicated to the symposium topic on the development of L-R asymmetry.